Royal London will set up its EU base in Ireland in order to remove the uncertainty created by the UK's triggering of Article 50.
The life insurance, pensions and investment firm said today it already has an Irish subsidiary and plans to convert operations into a domiciled business.
The firm said in a statement:
“Royal London has a successful and growing business in Ireland which we have operated under EU passporting rules to date.
By domiciling the business in Ireland we can remove much of the uncertainty triggered by the Brexit negotiations and continue to grow our business. We are in the early stages of discussions with the Central Bank of Ireland.
Earlier this morning Royal London's chief exec Phil Loney let slip to Reuters plans of the Irish move.
He said: "We will be domiciling a subsidiary in Ireland so we can continue to operate."
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Yesterday, the UK kicked off the formal process of divorcing itself from the EU, a process that will conclude within two years.
City firms will need to set a base "onshore" in the EU in order to sell products to customers on the mainland if the UK does not have access to the Single Market.
Many firms laid down contingency plans prior to the Brexit vote in June and have been working away at them ever since the referendum.